Brake disc for a vehicle disc brake

Abstract

Brake disc for a vehicle disc brake, comprising a radially inner hub portion ( 1 a ) intended to be non-rotatably joined to a wheel hub and a surrounding, radially outer disc portion with oppositely facing friction surfaces. The outer disc portion is formed of two disc elements ( 4 ) joined to the hub portion, which are separated by spacers ( 7 a– 7 d ), which define passages for cooling air.

1. Brake disc for a vehicle disc brake, comprising a radially inner hub portion ( 1   a ) intended to be non-rotatably joined to a wheel hub, a surrounding, radially outer disc portion ( 4 ) with oppositely facing friction surfaces ( 5 ), and passages ( 8 ,  9 ) disposed in the outer disc portion, said passages being arranged to guide cooling air in a disc material between the friction surfaces, characterized in that all the passages ( 8 ,  9 ) have inlets and outlets for cooling air at a radially outermost periphery of the outer disc portion, and that said passages do not penetrate into the hub portion, and in that the outer disc portion is formed by two disc elements ( 4 ) joined to the hub portion, said disc elements being separated by a plurality of individual, circumferentially spaced apart spacer elements ( 7   a – 7   d ), which define said passages ( 8 ,  9 ) extending between adjacent spacer elements, wherein the spacer elements are in the form of plural concentric rows of pillars, and the passage inlets are remote from a radially inner periphery of the outer disc portion. 
   
   
     2. Brake disc according to  claim 1 , characterized in that the hub portion ( 1   a ) has an inner periphery, which is provided with splines ( 2 ) intended to engage corresponding splines on the wheel hub. 
   
   
     3. Brake disc according to  claim 1 , characterized in that the hub portion ( 1   b ) is made with a flange ( 14 ) provided with borings ( 13 ) for screwing it securely to a fixing flange on a wheel hub. 
   
   
     4. Brake disc for a vehicle disc brake, comprising a radially inner hub portion ( 1   a ) intended to be non-rotatably joined to a wheel hub, a surrounding, radially outer disc portion ( 4 ) with oppositely facing friction surfaces ( 5 ), and passages ( 8 ,  9 ) disposed in the outer disc portion, said passages being arranged to guide cooling air in a disc material between the friction surfaces, characterized in that all the passages ( 8 ,  9 ) have inlets and outlets for cooling air only at a radially outermost periphery of the outer disc portion, and that said passages do not penetrate into the hub portion, and in that the outer disc portion is formed by two disc elements ( 4 ) joined to the hub portion, said disc elements being separated by a plurality of individual, circumferentially spaced apart spacer elements ( 7   a – 7   d ), which define said passages ( 8 ,  9 ) extending between adjacent spacer elements, wherein the spacer elements are in the form of plural concentric rows of pillars, and the passage inlets are remote from a radially inner periphery of the outer disc portion. 
   
   
     5. Brake disc according to  claim 4 , characterized in that the hub portion ( 1   a ) has an inner periphery, which is provided with splines ( 2 ) intended to engage corresponding splines on the wheel hub. 
   
   
     6. Brake disc according to  claim 4 , characterized in that the hub portion ( 1   b ) is made with a flange ( 14 ) provided with borings ( 13 ) for screwing it securely to a fixing flange on a wheel hub.